The association between coffee consumption and serum cholesterol concentration was studied in a cross-sectional epidemiological study among 5704 men and women in Finland. The mean serum cholesterol values of those consuming boiled coffee (24% of the subjects) was significantly higher than that of drinkers of filtered coffee (69% of the subjects) in both sexes after adjusting for age, body mass index, smoking, serum gamma-glutamyltransferase, index of saturated fat intake, and physical activity: in men 6.37 versus 6.02 mmol/l, in women 6.22 versus 5.84 mmol/l, both significant at p less than 0.001. A significant dose-dependent effect was observed between the consumption of boiled coffee both in men and in women. For filter coffee drinkers a weak coffee dose-cholesterol association was found only for women. The magnitude of the effect of boiled coffee, 0.3-0.4 mmol/l in serum cholesterol values, is in accordance with the results from controlled trials carried out among both hyper- and normocholesterolaemic subjects.